Metal negative electrode ultrasonic charging

ABSTRACT

Provided herein arc systems and methods for using an ultrasonic vibration generator to apply vibrational energy to a metal negative electrode of a rechargeable battery. In some examples, the application of vibrational energy to the metal negative electrode occurs during a charging event.

This application claims priority to U.S. Provisional Application No.62/470,069 filed on Mar. 10, 2017, which is incorporated by referenceherein in its entirety for all purposes.

FIELD

The present disclosure concerns secondary batteries and methods ofcharging and discharging secondary batteries.

BACKGROUND

Ultrasonic vibration has been used for micro-metal forming applications.For example, aluminum, or other metal, yield strength reduces as afunction of the vibration energy applied thereto. When energy is appliedto a metal via ultrasonic vibration, the metal is observed to behavelike a metal at an elevated temperature.

Some researchers have applied mechanical excitation to liquid stateelectrochemical cells in Pb-acid batteries, e.g., US20060051659A1 forthe purpose of causing preferential formation of ionic bonds versuscovalent bonds in an electrode. Other researchers have appliedultrasonic energy to interact with and enhance (i.e., speed up)electrochemical reaction rates at the electrode-electrolyte interface,which take place within and on the surface of the battery's electrodes.See, for example,http://www.activegridtech.com/wp-content/uploads/2012/03/BattCon-2012-AGT-Presentation.pdfThe application of ultrasonic energy in this instance reduces kineticionic inefficiencies which result in system impedance imbalances (i.e.,impedance mismatch) with the intention of producing a more efficientenergy conversion system.

Solid state batteries such as lithium metal batteries have a higherenergy density and lower cost than any commercial rechargeable batterypresently available. However, batteries with lithium metal anodes oftensuffer from dendrite formation during charging, which cause unsafefailures and short-circuits. Further, batteries with lithium metal mayneed to operate under high and uniform pressure. See, for example, U.S.Pat. No. 6,835,492. Applying a high and uniform pressure is a challengewhen the pressure application device is in a form factor that must besmall and light. Thus, improvements in the relevant field are needed.

Sonication techniques have not been applied to solid state batteries,due to a variety of concerns. Solid state batteries include a solidelectrolyte which separates the positive and negative electrodes. Thissolid electrolyte can be a thin film or a pressed pellet of a solidelectrolyte (e.g., a lithium stuffed garnet electrolyte). Because asonication device would likely consume valuable volume and weight in abattery pack, which in turn would dilute the energy density in a givenbattery pack, sonication devices have not been combined withrechargeable batteries such as Li-ion batteries, at least not in acommercially viable manner, to date. Energy density is a key metric fora battery system (e.g., automotive battery pack) and there has beenlittle motivation to incorporate a sonication device with solid statebatteries since such a device is likely to reduce the energy density perweight or per volume. In addition, a sonication device requires energyto operate. The energy required to operate the sonication device is notavailable to perform other useful work on a system such as thedrive-train of a car. Also, a sonication device could potentiallyfracture a brittle solid electrolyte in a solid state battery, resultingin device failure. Thus, there is a need in the relevant art for methodsand systems for combining sonication devices with rechargeablebatteries, including solid state batteries.

Accordingly, there is a need for improved systems and methods forcharging lithium metal anodes, for combining sonication devices withrechargeable solid-state batteries, and for preventing Li dendriteformation in electrochemical cells. The instant disclosure providessystems and methods to charge a battery with a lithium metal negativeelectrode safely by applying mechanical energy (e.g., vibrationalenergy) to an electrochemical cell.

SUMMARY

In one embodiment, set forth herein are methods for ultrasonicallyvibrating a metal negative electrode, including providing anelectrochemical cell, wherein the electrochemical cell includes apositive electrode, a solid electrolyte, and a metal negative electrode.The methods include vibrating the metal negative electrode (e.g., a Limetal negative electrode) ultrasonically, and charging theelectrochemical cell.

In a second embodiment, set forth herein is a method of charging abattery having a metal negative electrode, the method comprisingproviding a battery having less than a full charge; vibrating thebattery at ultrasonic frequencies; and charging the battery.

In a third embodiment, set forth herein is a system for performing amethod set forth herein.

In a fourth embodiment, set forth herein is an electrochemical cellhaving a metal negative electrode made by a method set forth herein.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIG. 1 shows an electrochemical cell (100) having a positive electrode(101), a solid electrolyte (102), and a metal negative electrode (103).

FIG. 2 shows a coin cell (202) having a metal negative electrode with apiezoelectric ultrasonic vibration generator (201) attached to an outeredge.

FIG. 3 shows a can cell (302) having a metal negative electrode with apiezoelectric ultrasonic vibration generator (301) attached to an outeredge.

FIG. 4 shows electrochemical cycle 1 from Example 2.

FIG. 5 shows electrochemical cycle 2 from Example 2.

FIG. 6 shows lithium (Li) applied to a solid state separator beforesonication.

FIG. 7 shows Li applied to a solid state separator after sonication. Thescale bar in FIG. 7 is 500 μm.

DETAILED DESCRIPTION I. General

The disclosure herein sets forth the use of an ultrasonic vibrationgenerator (e.g., piezo-electric actuator or other sources of vibration)to apply vibrational energy to the negative electrode side of a battery.In some examples, the application of vibrational energy to the negativeelectrode side of a battery occurs during a charging event. The input ofenergy via ultrasonic vibration locally increases the energy of themetal negative electrode and creates a softer metal as if the metal wereheated. In some examples, the vibrational energy is applied through thebattery starting from the positive electrode side of the battery. Insome examples, the vibrational energy is applied through the batterystarting from the negative electrode side of the battery. In someexamples, the vibrational energy is ultrasonication energy.

II. Definitions

As used herein, the term “about,” when qualifying a number, e.g., 15%w/w, refers to the number qualified and optionally the numbers includedin a range about that qualified number that includes ±10% of the number.For example, about 15% w/w includes 15% w/w as well as 13.5% w/w, 14%w/w, 14.5% w/w, 15.5% w/w, 16% w/w, or 16.5% w/w. For example, “about75° C.,” includes 75° C. as well 68° C., 69° C., 70° C., 71° C., 72° C.,73° C., 74° C., 75° C., 76° C., 77° C., 78° C., 79° C., 80° C., 81° C.,82° C., or 83° C.

As used herein, “selected from the group consisting of” refers to asingle member from the group, more than one member from the group, or acombination of members from the group. A member selected from the groupconsisting of A, B, and C includes, for example, A only, B only, or Conly, as well as A and B, A and C, B and C, as well as A, B, and C.

As used herein, the phrases “electrochemical cell” or “battery cell”shall mean a single cell including a positive electrode and a negativeelectrode, which have ionic communication between the two using anelectrolyte. In some embodiments, the same battery cell includesmultiple positive electrodes and/or multiple negative electrodesenclosed in one container.

As used herein, the terms “positive electrode” and “negative electrode”refer to the electrodes of a battery. During a charge cycle in aLi-secondary battery, Li ions leave the positive electrode and movethrough an electrolyte, to the negative electrode. During a chargecycle, electrons leave the positive electrode and move through anexternal circuit to the negative electrode. During a discharge cycle ina Li-secondary battery, Li ions migrate towards the positive electrodethrough an electrolyte and from the negative electrode. During adischarge cycle, electrons leave the negative electrode and move throughan external circuit to the positive electrode.

As used herein the phrase “electrochemical stack,” refers to one or moreunits which each include at least a negative electrode (e.g., Li, LiC₆),a positive electrode (e.g., Li-nickel-manganese-oxide, nickel manganesecobalt oxide (NMC), nickel cobalt aluminum oxide (NCA), or FeF₃,optionally combined with a solid state electrolyte or a gelelectrolyte), and a solid electrolyte (e.g., an oxide electrolyte setforth herein) between and in contact with the positive and negativeelectrodes. In some examples, between the solid electrolyte and thepositive electrode, there is an additional layer comprising a gelelectrolyte such as, e.g., a gel electrolyte described in PCTInternational Patent Application Publication No. WO 2017/197406,published on Nov. 16, 2017, titled “SOLID ELECTROLYTE SEPARATOR BONDINGAGENT”, which gel electrolytes are incorporated by reference herein intheir entirety for all purposes. An electrochemical stack may includeone of these aforementioned units. An electrochemical stack may or maynot include a positive current collector and/or a negative currentcollector. An electrochemical stack may include several of theseaforementioned units arranged in electrical communication (e.g., serialor parallel electrical connection). In some examples, when theelectrochemical stack includes several units, the units are layered orlaminated together in a column. In some examples, when theelectrochemical stack includes several units, the units are layered orlaminated together in an array. In some examples, when theelectrochemical stack includes several units, the stacks are arrangedsuch that one negative electrode is shared with two or more positiveelectrodes. Alternatively, in some examples, when the electrochemicalstack includes several units, the stacks are arranged such that onepositive electrode is shared with two or more negative electrodes.Unless specified otherwise, an electrochemical stack includes at leastone positive electrode, at least one solid electrolyte, and at least onenegative electrode, and optionally includes a gel electrolyte layerbetween the positive electrode and the solid electrolyte.

As used herein, the term “electrolyte,” refers to an ionicallyconductive and electrically insulating material. Electrolytes are usefulfor electrically insulating the positive and negative electrodes of asecondary battery while allowing for the conduction of ions, e.g., Li⁺,through the electrolyte. In some of the electrochemical devicesdescribed herein, the electrolyte includes a solid film, pellet, ormonolith of a Li⁺ conducting oxide, such as a lithium-stuffed garnet. Insome examples, the electrolyte further includes a gel electrolyte whichis laminated to or directly contacts the solid film, pellet, ormonolith. As used herein, the phrase “lithium stuffed garnet” refers tooxides that are characterized by a crystal structure related to a garnetcrystal structure. U.S. Patent Application Publication No. U.S.2015/0099190, which published Apr. 9, 2015 and was filed Oct. 7, 2014 asSer. No. 14/509,029, is incorporated by reference herein in its entiretyfor all purposes. This application describes Li-stuffed garnetsolid-state electrolytes used in solid-state lithium rechargeablebatteries. These Li-stuffed garnets generally having a compositionaccording to Li_(A)La_(B)M′_(C)M″_(D)Zr_(E)O_(F),Li_(A)La_(B)M′_(C)M″_(D)Ta_(E)O_(F), orLi_(A)La_(B)M′_(C)M″_(D)Nb_(E)O_(F), wherein 4<A<8.5, 1.5<B<4, 0≤C≤2,0≤D≤2; 0≤E<2, 10<F<13, and M′ and M″ are each, independently in eachinstance selected from Al, Mo, W, Nb, Sb, Ca, Ba, Sr, Ce, Hf, Rb, or Ta,or Li_(a)La_(b)Zr_(c)Al_(d)Me″_(e)O_(f), wherein 5<a<8.5; 2<b<4;0<c≤2.5; 0≤d≤2; 0≤e<2, and 10<f<13 and Me″ is a metal selected from Nb,Ta, V, W, Mo, or Sb and as otherwise described in U.S. PatentApplication Publication No. U.S. 2015/0099190. As used herein,lithium-stuffed garnets, and garnets, generally, include, but are notlimited to, Li_(7.0)La₃(Zr_(t1)+Nb_(t2)+Ta_(t3))O₁₂+0.35Al₂O₃; wherein(subscripts t1+t2+t3=subscript 2) so that the La:(Zr/Nb/Ta) ratio is3:2. Also, garnets used herein include, but are not limited to,Li_(x)La₃Zr₂O_(F)+yAl₂O₃, wherein x ranges from 5.5 to 9; and y rangesfrom 0 to 1. In these examples, subscripts x, y, and F are selected sothat the garnet is charge neutral. In some examples x is about 7 and yis about 1. In some examples x is 7 and y is 1.0. In some examples, x is5 and y is 1.0. In some examples, x is 6 and y is 1.0. In some examples,x is 8 and y is 1.0. In some examples, x is 9 and y is 1.0. In someexamples x is 7 and y is 0.35. In some examples, x is 5 and y is 0.35.In some examples, x is 6 and y is 0.35. In some examples, x is 8 and yis 0.35. In some examples, x is 9 and y is 0.35. In some examples x is 7and y is 0.7. In some examples, x is 5 and y is 0.7. In some examples, xis 6 and y is 0.7. In some examples, x is 8 and y is 0.7. In someexamples, x is 9 and y is 0.7. In some examples x is 7 and y is 0.75. Insome examples, x is 5 and y is 0.75. In some examples, x is 6 and y is0.75. In some examples, x is 8 and y is 0.75. In some examples, x is 9and y is 0.75. In some examples x is 7 and y is 0.8. In some examples, xis 5 and y is 0.8. In some examples, x is 6 and y is 0.8. In someexamples, x is 8 and y is 0.8. In some examples, x is 9 and y is 0.8. Insome examples x is 7 and y is 0.5. In some examples, x is 5 and y is0.5. In some examples, x is 6 and y is 0.5. In some examples, x is 8 andy is 0.5. In some examples, x is 9 and y is 0.5. In some examples x is 7and y is 0.4. In some examples, x is 5 and y is 0.4. In some examples, xis 6 and y is 0.4. In some examples, x is 8 and y is 0.4. In someexamples, x is 9 and y is 0.4. In some examples x is 7 and y is 0.3. Insome examples, x is 5 and y is 0.3. In some examples, x is 6 and y is0.3. In some examples, x is 8 and y is 0.3. In some examples, x is 9 andy is 0.3. In some examples x is 7 and y is 0.22. In some examples, x is5 and y is 0.22. In some examples, x is 6 and y is 0.22. In someexamples, x is 8 and y is 0.22. In some examples, x is 9 and y is 0.22.Also, garnets as used herein include, but are not limited to,Li_(x)La₃Zr₂O₁₂+yAl₂O₃. In one embodiment, the Li-stuffed garnet hereinhas a composition of Li₇Li₃Zr₂O₁₂. In another embodiment, the Li-stuffedgarnet herein has a composition of Li₇Li₃Zr₂O_(12·)Al₂O₃. In yet anotherembodiment, the Li-stuffed garnet herein has a composition ofLi₇Li₃Zr₂O₁₂·0.22Al₂O₃. In yet another embodiment, the Li-stuffed garnetherein has a composition of Li₇Li₃Zr₂O₁₂·0.35Al₂O₃. In certain otherembodiments, the Li-stuffed garnet herein has a composition ofLi₇Li₃Zr₂O₁₂·0.5Al₂O₃. In another embodiment, the Li-stuffed garnetherein has a composition of Li₇Li₃Zr₂O₁₂·0.75Al₂O₃.

As used herein, garnet does not include YAG-gamets (i.e., yttriumaluminum garnets, or, e.g., Y₃Al₅O₁₂). As used herein, garnet does notinclude silicate-based garnets such as pyrope, almandine, spessartine,grossular, hessonite, or cinnamon-stone, tsavorite, uvarovite andandradite and the solid solutions pyrope-almandine-spessarite anduvarovite-grossular-andradite. As used herein, garnets do not includenesosilicates having the general formula X₃Y₂(SiO₄)₃ wherein X is Ca,Mg, Fe, and, or, Mn; and Y is Al, Fe, and, or, Cr.

As used herein the phrase “garnet-type electrolyte,” refers to anelectrolyte that includes a lithium stuffed garnet material describedherein as the Li⁺ ion conductor. The advantages of Li-stuffed garnetsolid-state electrolytes are many, including as a substitution forliquid, flammable electrolytes commonly used in lithium rechargeablebatteries.

As used herein, the phrase “inorganic solid state electrolyte,” refersto a material not including carbon which conducts ions (e.g., Li⁺) butdoes not conduct electrons. Non-limiting examples of inorganic solidstate electrolytes include oxide electrolytes and sulfide electrolytes,which are further described in the instant disclosure.

As used herein, the phrase “directly contacts,” refers to thejuxtaposition of two materials such that the two materials contact eachother sufficiently to conduct either an ion or electron current. As usedherein, direct contact may also refer to two materials in contact witheach other and which do not have any other different types of solid orliquid materials positioned between the two materials which are indirect contact.

In some examples, the electrolytes herein may include, or be layeredwith, or be laminated to, or contact a sulfide electrolyte. As usedherein, the phrase “sulfide electrolyte,” includes, but is not limitedto, electrolytes referred to herein as LATS, LSS, LTS, LXPS, or LXPSO,where X is Si, Ge, Sn, As, Al. In these acronyms (LSS, LTS, LXPS, orLXPSO), S refers to the element S, Si, or combinations thereof, and Trefers to the element Sn. “Sulfide electrolyte” may also includeLi_(a)P_(b)S_(c)X_(d), Li_(a)B_(b)S_(c)X_(d), Li_(a)Sn_(b)S_(c)X_(d) orLi_(a)Si_(b)S_(c)X_(d) where X=F, Cl, Br, I, and 10%≤a≤50%, 10%≤b≤44%,24%≤c≤70%, 0≤d≤18%.

In some examples, the sulfide electrolyte layer is a material containingSi, Li, O, P, and S and is referred to herein as a SLOPS material. Insome examples, the electrolyte layer is a material containing Si, Li, O,P, and S and is referred to herein as a SLOPS/LSS material. As usedherein, LSS includes, unless otherwise specified, a 60:40 molar ratioLi₂S:SiS₂.

As used herein, “SLOPS” includes, unless otherwise specified, a 60:40molar ratio of Li₂S:SiS₂ with 0.1-10 mol. % Li₃PO₄. In some examples,“SLOPS” includes Li₁₀Si₄Si₃ (50:50 Li₂S:SiS₂) with 0.1-10 mol. % Li₃PO₄.In some examples, “SLOPS” includes Li₂₆Si₇S₂₇ (65:35 Li₂S:SiS₂) with0.1-10 mol. % Li₃PO₄. In some examples, “SLOPS” includes Li₄SiS₄ (67:33Li₂S:SiS₂) with 0.1-5 mol. % Li₃PO₄. In some examples, “SLOPS” includesLi₄Si₃S₁₃ (70:30 Li₂S:SiS₂) with 0.1-5 mol. % Li₃PO₄. In some examples,“SLOPS” is characterized by the formula (1−x)(60:40Li₂S:SiS₂)*(x)(Li₃PO₄), wherein x is from 0.01 to 0.99. As used herein,“LBS-PDX” refers to an electrolyte composition of Li₂S:B₂S₃:Li₃PO₄:LiXwhere X is a halogen (X=F, Cl, Br, I). The composition can includeLi₃BS₃ or LisB₇S₁₃ doped with 0-30% lithium halide such as LiI and/or0-10% Li₃PO₄.

As used herein, “LSS” refers to lithium silicon sulfide which can bedescribed as Li₂S—SiS₂, Li—SiS₂, Li—S—Si, and/or a catholyte consistingessentially of Li, S, and Si. LSS refers to an electrolyte materialcharacterized by the formula Li_(x)Si_(y)S_(z) where 0.33≤x≤0.5,0.1≤y≤0.2, 0.4≤z≤0.55, and it may include up to 10 atomic % oxygen. LSSalso refers to an electrolyte material comprising Li, Si, and S. In someexamples, LSS is a mixture of Li₂S and SiS₂. In some examples, the ratioof Li₂S:SiS₂ is 90:10, 85:15, 80:20, 75:25, 70:30, 2:1, 65:35, 60:40,55:45, or 50:50 molar ratio. LSS may be doped with compounds such asLi_(x)PO_(y), Li_(x)BO_(y), Li₄SiO₄, Li₃MO₄, Li₃MO₃, PS_(x), and/orlithium halides such as, but not limited to, LiI, LiCl, LiF, or LiBr,wherein 0<x≤5 and 0<y≤5.

As used herein, “LTS” refers to a lithium tin sulfide compound which canbe described as Li₂S:SnS₂:As₂S₅, Li₂S—SnS₂, Li₂S—SnS, Li—S—Sn, and/or acatholyte consisting essentially of Li, S, and Sn. The composition maybe Li_(x)Sn_(y)S_(z) where 0.25≤x≤0.65, 0.05≤y≤0.2, and 0.25≤z≤0.65. Insome examples, LTS is a mixture of Li₂S and SnS₂ in the ratio of 80:20,75:25, 70:30, 2:1, or 1:1 molar ratio. LTS may include up to 10 atomic %oxygen. LTS may be doped with Bi, Sb, As, P, B, Al, Ge, Ga, and/or Inand/or lithium halides such as, but not limited to, LiI, LiCl, LiF, orLiBr, As used herein, “LATS” refers to LTS, as used above, and furthercomprising Arsenic (As).

As used herein, “LXPS” refers to a material characterized by the formulaLiaMPbSc, where M is Si, Ge, Sn, and/or Al, and where 2≤a≤8, 0.5≤b≤2.5,4≤c≤12. “LSPS” refers to an electrolyte material characterized by theformula LaSiPbSc, where 2≤a≤8, 0.5≤b≤2.5, 4≤c≤12. LSPS refers to anelectrolyte material characterized by the formula LaSiPbSc, wherein,where 2≤a≤8, 0.5≤b≤4≤c≤12, d<3. In these examples, the subscripts areselected so that the compound is neutrally charged. Exemplary LXPSmaterials are found, for example, in PCT International PatentApplication Publication No. WO 2014/186634, which published on Nov. 20,2014, titled “SOLID STATE CATHOLYTE OR ELECTROLYTE FOR BATTERY USINGLIAMPBSC (M=Si, Ge, AND/OR Sn)”, which is incorporated by referenceherein in its entirety for all purposes. When M is Sn and Si—both arepresent—the LXPS material is referred to as LSTPS. As used herein,“LSTPSO,” refers to LSTPS that is doped with, or has, O present. In someexamples, “LSTPSO,” is a LSTPS material with an oxygen content between0.01 and 10 atomic %. “LSPS,” refers to an electrolyte material havingLi, Si, P, and S chemical constituents. As used herein “LSTPS,” refersto an electrolyte material having Li, Si, P, Sn, and S chemicalconstituents. As used herein, “LSPSO,” refers to LSPS that is dopedwith, or has, O present. In some examples, “LSPSO,” is a LSPS materialwith an oxygen content between 0.01 and 10 atomic %. As used herein,“LATP,” refers to an electrolyte material having Li, As, Sn, and Pchemical constituents. As used herein “LAGP,” refers to an electrolytematerial having Li, As, Ge, and P chemical constituents. As used herein,“LXPSO” refers to an electrolyte material characterized by the formulaLiaMPbScOd, where M is Si, Ge, Sn, and/or Al, and where 2≤a≤8,0.5≤b≤2.5, 4≤c≤12, d<3. LXPSO refers to LXPS, as defined above, andhaving oxygen doping at from 0.1 to about 10 atomic %. LPSO refers toLPS, as defined above, and having oxygen doping at from 0.1 to about 10atomic %.

As used herein, “LPS,” refers to an electrolyte having Li, P, and Schemical constituents. As used herein, “LPSO,” refers to LPS that isdoped with or has O present. In some examples, “LPSO,” is a LPS materialwith an oxygen content between 0.01 and 10 atomic %. LPS refers to anelectrolyte material that can be characterized by the formulaLi_(x)P_(y)S_(z) where 0.33≤x≤0.67, 0.07≤y≤0.2 and 0.4≤z≤0.55. LPS alsorefers to an electrolyte characterized by a product formed from amixture of Li₂S:P₂S₅ wherein the molar ratio is 10:1, 9:1, 8:1, 7:1, 6:15:1, 4:1, 3:1, 7:3, 2:1, or 1:1. LPS also refers to an electrolytecharacterized by a product formed from a mixture of Li₂S:P₂S₅ whereinthe reactant or precursor amount of Li₂S is 95 atomic % and P₂S₅ is 5atomic %. LPS also refers to an electrolyte characterized by a productformed from a mixture of Li₂S:P₂S₅ wherein the reactant or precursoramount of Li₂S is 90 atomic % and P₂S₅ is 10 atomic %. LPS also refersto an electrolyte characterized by a product formed from a mixture ofLi₂S:P₂S₅ wherein the reactant or precursor amount of Li₂S is 85 atomic% and P₂S₅ is 15 atomic %. LPS also refers to an electrolytecharacterized by a product formed from a mixture of Li₂S:P₂S₅ whereinthe reactant or precursor amount of Li₂S is 80 atomic % and P₂S₅ is 20atomic %. LPS also refers to an electrolyte characterized by a productformed from a mixture of Li₂S:P₂S₅ wherein the reactant or precursoramount of Li₂S is 75 atomic % and P₂S₅ is 25 atomic %. LPS also refersto an electrolyte characterized by a product formed from a mixture ofLi₂S:P₂S₅ wherein the reactant or precursor amount of Li₂S is 70 atomic% and P₂S₅ is 30 atomic %. LPS also refers to an electrolytecharacterized by a product formed from a mixture of Li₂S:P₂S₅ whereinthe reactant or precursor amount of Li₂S is 65 atomic % and P₂S₅ is 35atomic %. LPS also refers to an electrolyte characterized by a productformed from a mixture of Li₂S:P₂S₅ wherein the reactant or precursoramount of Li₂S is 60 atomic % and P₂S₅ is 40 atomic %. LPS may also bedoped with a lithium halide such as LiF, LiCl, LiBr, or LiI at a 0-40%molar content.

As used herein, “LBS” refers to an electrolyte material characterized bythe formula Li_(a)B_(b)S_(c) and may include oxygen and/or a lithiumhalide (LiF, LiCl, LiBr, LiI) at 0-40 mol %.

As used herein, “LPSO” refers to an electrolyte material characterizedby the formula Li_(x)P_(y)S_(z)O_(w) where 0.33≤x≤0.67, 0.07≤y≤0.2,0.4≤z≤0.55, 0≤w≤0.15. Also, LPSO refers to LPS, as defined above, thatincludes an oxygen content of from 0.01 to 10 atomic %. In someexamples, the oxygen content is 1 atomic %. In other examples, theoxygen content is 2 atomic %. In some other examples, the oxygen contentis 3 atomic %. In some examples, the oxygen content is 4 atomic %. Inother examples, the oxygen content is 5 atomic %. In some otherexamples, the oxygen content is 6 atomic %. In some examples, the oxygencontent is 7 atomic %. In other examples, the oxygen content is 8 atomic%. In some other examples, the oxygen content is 9 atomic %. In someexamples, the oxygen content is 10 atomic %.

As used herein, the term “LBHI” refers to a lithium conductingelectrolyte comprising Li, B, H, and I. LBHI includes a compound havingthe formula aLiBH₄+bLiX where X=Cl, Br, and/or I and where a:b=7:1, 6:1,5:1, 4:1, 3:1, 2:1, or within the range a/b=2-4. LBHI may furtherinclude nitrogen in the form of compound having the formulaaLiBH₄₊bLiX+cLiNH₂ where (a+c)/b=2-4 and c/a=0-10. Non-limiting examplesof LBHI include LBHI described in PCT International Patent Applicationnumber PCT/US2017/057735 filed on Oct. 20, 2017, which disclosure isincorporated by reference herein in its entirety for all purposes.

As used herein, the term “LPSI” refers to a lithium conductingelectrolyte comprising Li, P, S, and I. LPSI includes a compound havingthe formula aLi2S+bP2Sy+cLiX where X=Cl, Br, and/or I and where y=3-5and where a/b=2.5-4.5 and where (a+b)/c=0.5-15. Non-limiting examples ofLPSI include LPSI described in PCT International Patent ApplicationPublication No. WO 2017/096088, which published on Jun. 8, 2017, titled“LITHIUM, PHOSPHORUS, SULFUR, AND IODINE INCLUDING ELECTROLYTE ANDCATHOLYTE COMPOSITIONS, ELECTROLYTE MEMBRANES FOR ELECTROCHEMICALDEVICES, AND ANNEALING METHODS OF MAKING THESE ELECTROLYTES ANDCATHOLYTES”, which disclosure is incorporated by reference herein in itsentirety for all purposes.

Also contemplated are instances where any of the aforementionedelectrolytes may be catholytes.

As used herein, the term “LIRAP” refers to a lithium rich antiperovskiteand is used synonymously with “LOC” or “Li₃OCl”. The composition ofLIRAP is aLi₂O+bLiX+cLiOH+dAl₂O₃ where X=Cl, Br, and/or I, a/b=0.7-9,c/a=0.01-1, d/a=0.001-0.1.

As used herein, the phrase “ultrasonically vibrating a metal negativeelectrode,” or “vibrating,” unless specified otherwise to the contrary,refer to the application of ultrasonic vibrational energy to a metalnegative electrode in an electrochemical cell. The vibrating may occurbefore, during, or after a charging event. The frequency of vibrationcan be modulated to accommodate a variety of charging scenarios.

As used herein, the phrase “SOC” refers to a battery state-of-charge asa percentage of full charge. When a battery is fully charged, its SOC is100%; when a battery is fully discharged, its SOC is 0%; when a batteryis half-charged, its SOC is 50%. SOC may be determined by measuringcharge passed over time, voltage, voltage hysteresis, impedance,temperature, pressure, or any other metric which is indicative of theSOC.

As used herein, the phrase “full charge,” refers to an electrochemicalcell having a 100% state-of-charge (SOC). As used herein, the phrase“less than a full charge,” refers to an electrochemical cell having aSOC less than 100%. Full charge may be relative to a rated or nameplatecapacity of the battery when measured at beginning of life at aspecified rate and temperature.

As used herein, the term “charging,” or the phrase “charging theelectrochemical cell,” unless specified otherwise to the contrary, referto a process whereby energy is applied to an electrochemical cell inorder to increase its SOC. Charging typically involves applying a highvoltage to the battery in a polarity that causes positive ions to flowfrom the positive electrode to the negative electrode.

III. Methods

Set forth herein are unique methods of applying energy to a metalnegative electrode in an electrochemical cell during the chargingprocess. In an example, set forth herein is a method for ultrasonicallyvibrating a metal negative electrode, wherein the method includes (1)providing an electrochemical cell, which includes a metal negativeelectrode; and (2) vibrating the metal negative electrodeultrasonically. In an example, set forth herein is a method forultrasonically vibrating a metal negative electrode, wherein the methodincludes (1) providing an electrochemical cell, which includes a metalnegative electrode; (2) vibrating the metal negative electrodeultrasonically; and (3) charging the electrochemical cell. In anexample, set forth herein is a method for ultrasonically vibrating ametal negative electrode, wherein the method includes (1) providing anelectrochemical cell, which includes a positive electrode, a solidelectrolyte, and a metal negative electrode; (2) vibrating the metalnegative electrode ultrasonically; and (3) charging the electrochemicalcell. In any of the said methods, in one example, the metal negativeelectrode is a lithium (Li) metal negative electrode. In any of the saidmethods, in one example, the metal negative electrode is a sodium (Na)metal negative electrode. In any of the said methods, in one example,the metal negative electrode is a zinc (Zn) metal negative electrode.

In some examples, the vibrating and charging occur simultaneously. Insome other examples, the vibrating and charging occursequentially—vibrating and then charging, or charging and thenvibrating. In yet other examples, the vibrating and charging occursequentially and repeatedly, e.g., charging, vibrating, charging,vibrating, charging, and so forth. In yet other examples, the vibratingand charging occur sequentially and repeatedly for at least 10 repeatsof vibrating and charging. In yet other examples, the vibrating andcharging occur sequentially and repeatedly for at least 100 repeats ofvibrating and charging. In yet other examples, the vibrating andcharging occur sequentially and repeatedly for at least 1000 repeats ofvibrating and charging.

The methods described herein are applicable to coin cells, pouch cells,can cells, or any other suitable forms of cells, electrochemical cells,or batteries. The application of any mechanical energy (e.g.,vibrational energy) is effected, in some examples, by contacting theexterior surface of the cell with a suitable device (e.g., a sonicationdevice). In alternate embodiments, a suitable device (e.g., a sonicationdevice) may be placed inside the cell. In further embodiments, asuitable device (e.g., a sonication device) may contact the exteriorsurface of the cell and may also reside inside the cell. By way ofexample only, a sonication device may be a piezoelectric materialcontacting the exterior surface of the cell and/or placed inside thecell. In further embodiments, a suitable device (e.g., a sonicationdevice) may also be positioned in close proximity to the cell. In someexamples, a sonication device may be placed in a battery module, in abattery system, and/or in a battery pack.

In some examples, including any of the foregoing, the methods includecharging which occurs at a temperature lower than 80° C., 75° C., 70°C., 65° C., 60° C., 55° C., 50° C., 45° C., 40° C., 35° C., 30° C., 25°C., 20° C., 15° C., 10° C., 5° C., 0° C., −5° C., −10° C., −15° C., −20°C., −25° C., or −30° C. In certain examples, including any of theforegoing, the methods include charging which occurs at a temperaturelower than 80° C. In certain examples, including any of the foregoing,the methods include charging which occurs at a temperature lower than75° C. In certain examples, including any of the foregoing, the methodsinclude charging which occurs at a temperature lower than 70° C. Incertain examples, including any of the foregoing, the methods includecharging which occurs at a temperature lower than 65° C. In certainexamples, including any of the foregoing, the methods include chargingwhich occurs at a temperature lower than 60° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than 55° C. In certain examples, includingany of the foregoing, the methods include charging which occurs at atemperature lower than 50° C. In certain examples, including any of theforegoing, the methods include charging which occurs at a temperaturelower than 45° C. In certain examples, including any of the foregoing,the methods include charging which occurs at a temperature lower than40° C. In certain examples, including any of the foregoing, the methodsinclude charging which occurs at a temperature lower than 35° C. Incertain examples, including any of the foregoing, the methods includecharging which occurs at a temperature lower than 30° C. In certainexamples, including any of the foregoing, the methods include chargingwhich occurs at a temperature lower than 25° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than 20° C. In certain examples, includingany of the foregoing, the methods include charging which occurs at atemperature lower than 15° C. In certain examples, including any of theforegoing, the methods include charging which occurs at a temperaturelower than 10° C. In certain examples, including any of the foregoing,the methods include charging which occurs at a temperature lower than 5°C. In certain examples, including any of the foregoing, the methodsinclude charging which occurs at a temperature lower than 0° C. Incertain examples, including any of the foregoing, the methods includecharging which occurs at a temperature lower than 80° C. In certainexamples, including any of the foregoing, the methods include chargingwhich occurs at a temperature lower than −5° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than −10° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than −15° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than −20° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than −25° C. In certain examples,including any of the foregoing, the methods include charging whichoccurs at a temperature lower than −30° C. In some examples, thecharging occurs at least at a temperature of −30° C. or greater.

In some examples, including any of the foregoing, the metal negativeelectrode is a lithium (Li) metal negative electrode. In some of theseexamples, the Li negative electrode is selected from Li foil orevaporated Li. In some of these examples, the metal negative electrode(e.g., Li negative electrode) is deposited in the electrochemical cellduring charging. In some examples, the thickness of the metal negativeelectrode ranges from about 1, 2, 3, 4, 5, 10, 15, 20, 25, 30 jam toabout 5, 6, 7, 8, 9, 10, 15, 20, 30, 40, 50 Rm. In some instances, thethickness of the metal negative electrode is about 1 μm. In someinstances, the thickness of the metal negative electrode is about 2 μm.In some instances, the thickness of the metal negative electrode isabout 3 μm. In some instances, the thickness of the metal negativeelectrode is about 4 μm. In some instances, the thickness of the metalnegative electrode is about 5 μm. In some instances, the thickness ofthe metal negative electrode is about 6 μm. In some instances, thethickness of the metal negative electrode is about 7 μm. In someinstances, the thickness of the metal negative electrode is about 8 μm.In some instances, the thickness of the metal negative electrode isabout 9 μm. In some instances, the thickness of the metal negativeelectrode is about 10 μm. In some instances, the thickness of the metalnegative electrode is about 15 In some instances, the thickness of themetal negative electrode is about 20 μm. In some instances, thethickness of the metal negative electrode is about 25 μm. In someinstances, the thickness of the metal negative electrode is about 30 μm.In some instances, the thickness of the metal negative electrode isabout 35 μm. In some instances, the thickness of the metal negativeelectrode is about 40 μm. In some instances, the thickness of the metalnegative electrode is about 45 μm. In some instances, the thickness ofthe metal negative electrode is about 50 μm.

In some examples, including any of the foregoing, the metal negativeelectrode is a sodium (Na) metal negative electrode. In other examples,the metal negative electrode is a zinc (Zn) metal negative electrode.

In some examples, including any of the foregoing, the solid electrolyteis a sulfide-based electrolyte or a garnet-based electrolyte or aborohydride-based electrolyte. In certain examples, the solidelectrolyte is a sulfide-based electrolyte. In certain other examples,the solid electrolyte is a garnet-based electrolyte. In yet otherexamples, the solid electrolyte is a borohydride-based electrolyte.Examples of solid electrolytes include and are not limited to solidelectrolytes described in US Patent Application Publication No. US2015/0099188, which published on Apr. 9, 2015, titled “GARNET MATERIALSFOR LI SECONDARY BATTERIES AND METHODS OF MAKING AND USING GARNETMATERIALS”, US Patent Application Publication No. US 2015/0099190, whichpublished on Apr. 9, 2015, titled “GARNET MATERIALS FOR LI SECONDARYBATTERIES AND METHODS OF MAKING AND USING GARNET MATERIALS”, U.S. Pat.No. 9,172,114, which issued on Oct. 27, 2015, titled “SOLID STATECATHOLYTES AND ELECTROLYTES FOR ENERGY STORAGE DEVICES”, U.S. Pat. No.9,634,354, which issued on Apr. 25, 2017, titled “SOLID STATE CATHOLYTESAND ELECTROLYTES FOR ENERGY STORAGE DEVICES”, U.S. Pat. No. 9,553,332,which issued on Jan. 24, 2017, titled “SOLID STATE CATHOLYTES ANDELECTROLYTES FOR ENERGY STORAGE DEVICES” US Patent ApplicationPublication No. US 2014/0113187, which published on Apr. 24, 2014,titled “METHOD FOR FORMING AND PROCESSING ANTIPEROVSKITE MATERIAL DOPEDWITH ALUMINUM MATERIAL”, US Patent Application Publication No. US2017/0214084, which published on Jul. 27, 2017, titled “ANNEALED GARNETELECTROLYTE SEPARATORS”, PCT International Patent ApplicationPublication No. WO 2017/131676, which published on Aug. 3, 2017, titled“ANNEALED GARNET ELECTROLYTE SEPARATORS”, PCT International PatentApplication Publication No. WO 2017/096088, which published on Jun. 8,2017, titled “LITHIUM, PHOSPHORUS, SULFUR, AND IODINE INCLUDINGELECTROLYTE AND CATHOLYTE COMPOSITIONS, ELECTROLYTE MEMBRANES FORELECTROCHEMICAL DEVICES, AND ANNEALING METHODS OF MAKING THESEELECTROLYTES AND CATHOLYTES”, US Patent Application Publication No. US2017/0005367, which published on May 1, 2017, titled “COMPOSITEELECTROLYTES”, WO 2016/210371, which published on Dec. 29, 2016, titled“COMPOSITE ELECTROLYTES”, PCT International Patent Application No.PCT/US2017/057735, filed on Oct. 20, 2017, PCT International PatentApplication No. PCT/US2017/057462, filed on Oct. 19, 2017, and PCTInternational Patent Application No. PCT/US2017/057739, filed on Oct.20, 2017, each of which is incorporated by reference herein in itsentirety for all purposes.

In some examples, including any of the foregoing, the methods includeapplying a pressure to the metal negative electrode. In certainexamples, the applied pressure is at least 10, 20, 30, 40, 50, 60, 70,80, 90, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 2000, 3000,or 4000, pounds per square inch (PSI). In some examples, including anyof the foregoing, the methods include applying a pressure to the metalnegative electrode where the pressure is in a range of about 10, 20, 30,40 PSI to about 1000, 2000, 3000, 4000 PSI. In some of these examples,the pressure is 10 PSI. In some of these examples, the pressure is 20PSI. In some of these examples, the pressure is 10 PSI. In some of theseexamples, the pressure is 30 PSI. In some of these examples, thepressure is 40 PSI. In some of these examples, the pressure is 50 PSI.In some of these examples, the pressure is 60 PSI. In some of theseexamples, the pressure is 70 PSI. In some of these examples, thepressure is 80 PSI. In some of these examples, the pressure is 90 PSI.In some of these examples, the pressure is 100 PSI. In some of theseexamples, the pressure is 200 PSI. In some of these examples, thepressure is 300 PSI. In some of these examples, the pressure is 400 PSI.In some of these examples, the pressure is 500 PSI. In some of theseexamples, the pressure is 600 PSI. In some of these examples, thepressure is 700 PSI. In some of these examples, the pressure is 800 PSI.In some of these examples, the pressure is 900 PSI. In some of theseexamples, the pressure is 1000 PSI. In some of these examples, thepressure is 2000 PSI. In some of these examples, the pressure is 3000PSI. In some of these examples, the pressure is 4000 PSI.

In some examples, including any of the foregoing, the methods includeapplying a pressure to the metal negative electrode. In certainexamples, the pressure is at least 10, 20, 30, 40, 50, 60, 70, 80, 90,100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 2000, 3000, 4000,pounds per square inch (PSI). In some of these examples, the pressure isabout 10 PSI. In some of these examples, the pressure is about 20 PSI.In some of these examples, the pressure is 10 PSI. In some of theseexamples, the pressure is about 30 PSI. In some of these examples, thepressure is about 40 PSI. In some of these examples, the pressure isabout 50 PSI. In some of these examples, the pressure is about 60 PSI.In some of these examples, the pressure is about 70 PSI. In some ofthese examples, the pressure is about 80 PSI. In some of these examples,the pressure is about 90 PSI. In some of these examples, the pressure isabout 100 PSI. In some of these examples, the pressure is about 200 PSI.In some of these examples, the pressure is about 300 PSI. In some ofthese examples, the pressure is about 400 PSI. In some of theseexamples, the pressure is about 500 PSI. In some of these examples, thepressure is about 600 PSI. In some of these examples, the pressure isabout 700 PSI. In some of these examples, the pressure is about 800 PSI.In some of these examples, the pressure is about 900 PSI. In some ofthese examples, the pressure is about 1000 PSI. In some of theseexamples, the pressure is about 2000 PSI. In some of these examples, thepressure is about 3000 PSI. In some of these examples, the pressure isabout 4000 PSI.

In some examples, including any of the foregoing, the methods includeapplying a pressure to the metal negative electrode, wherein the appliedpressure is less than 1000, 600, 500, 400, 300, 200, 100, 90, 80, 70,60, 50, 40, 30, 20, or 10 PSI. In some of these examples, the pressureis less than 1000 PSI. In some of these examples, the pressure is lessthan 600 PSI. In some of these examples, the pressure is less than 500PSI. In some of these examples, the pressure is less than 400 PSI. Insome of these examples, the pressure is less than 300 PSI. In some ofthese examples, the pressure is less than 200 PSI. In some of theseexamples, the pressure is less than 100 PSI. In some of these examples,the pressure is less than 90 PSI. In some of these examples, thepressure is less than 80 PSI. In some of these examples, the pressure isless than 70 PSI. In some of these examples, the pressure is less than60 PSI. In some of these examples, the pressure is less than 50 PSI. Insome of these examples, the pressure is less than 40 PSI. In some ofthese examples, the pressure is less than 30 PSI. In some of theseexamples, the pressure is less than 20 PSI. In some of these examples,the pressure is less than 10 PSI. In some examples, the pressure is atleast 10 PSI.

In some examples, including any of the foregoing, the methods includevibrating and charging simultaneously.

In some examples, including any of the foregoing, the methods includecharging, first, and then, vibrating.

In some examples, including any of the foregoing, set forth herein is amethod of charging a battery having a metal negative electrode, whereinthe method includes providing a battery having less than a full charge;vibrating the battery at ultrasonic frequencies; and charging thebattery. In some of these examples, the pressure applied to the metalnegative electrode is 1000 PSI or less. In some of these examples, thepressure applied to the metal negative electrode is 600 PSI or less. Insome of these examples, the vibrating and charging occur concurrently.In some of these examples, the pressure applied to the metal negativeelectrode is 300 PSI or less. In some of these examples, the pressureapplied to the metal negative electrode is 200 PSI or less. In some ofthese examples, the pressure applied to the metal negative electrode is100 PSI or less. In some of these examples, the pressure applied to themetal negative electrode is 90 PSI or less. In some of these examples,the pressure applied to the metal negative electrode is 80 PSI or less.In some of these examples, the pressure applied to the metal negativeelectrode is 70 PSI or less. In some of these examples, the pressureapplied to the metal negative electrode is 60 PSI or less. In some ofthese examples, the pressure applied to the metal negative electrode is50 PSI or less. In some of these examples, the pressure applied to themetal negative electrode is 40 PSI or less. In some of these examples,the pressure applied to the metal negative electrode is 30 PSI or less.In some of these examples, the pressure applied to the metal negativeelectrode is 0 PSI or less. In some of these examples, the pressureapplied to the metal negative electrode is 10 PSI or less. In some ofthese examples, the pressure applied to the metal negative electrode is5 PSI or less. In some of these examples, the pressure applied to themetal negative electrode is at least 0.5 PSI.

In some examples, including any of the foregoing, set forth herein is amethod of charging a battery having a metal negative electrode, whereinthe method includes charging wherein the current at which the chargingoccurs is at least 1 mA/cm², 2 mA/cm², 3 mA/cm², 4 mA/cm², 5 mA/cm², 6mA/cm², or 10 mA/cm². In some examples, the current at which thecharging occurs is at least 1 mA/cm². In some examples, the current atwhich the charging occurs is at least 2 mA/cm². In some examples, thecurrent at which the charging occurs is at least 3 mA/cm². In someexamples, the current at which the charging occurs is at least 4 mA/cm².In some examples, the current at which the charging occurs is at least 5mA/cm². In some examples, the current at which the charging occurs is atleast 6 mA/cm². In some examples, the current at which the chargingoccurs is at least 10 mA/cm².

In some examples, including any of the foregoing, set forth herein is amethod of charging a battery having a metal negative electrode, whereinthe method includes charging wherein the current at which the chargingoccurs is at least C/5, C/4, C/3, C/2, 1C, 2C, 3C, 4C, 5C, or 10C rate.In some examples, the current at which the charging occurs is at leastC/5. In some examples, the current at which the charging occurs is atleast C/4. In some examples, the current at which the charging occurs isat least C/3. In some examples, the current at which the charging occursis at least C/2. In some examples, the current at which the chargingoccurs is at least 1C. In some examples, the current at which thecharging occurs is at least 2C. In some examples, the current at whichthe charging occurs is at least 3C. In some examples, the current atwhich the charging occurs is at least 4C. In some examples, the currentat which the charging occurs is at least 5C. In some examples, thecurrent at which the charging occurs is at least 10C.

IV. Electrodes

In some examples, set forth herein is an electrochemical cell having ametal negative electrode made by the method set forth herein. In someexamples, including any of the foregoing, the metal negative electrodeis a lithium (Li) metal negative electrode. In some of these examples,the Li negative electrode is selected from Li foil or evaporated Li. Insome of these examples, the Li negative electrode is deposited in theelectrochemical cell during charging. In some examples, the thickness ofthe lithium metal negative electrode is 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 10μm, 15 μm, 20 μm, 25 μm, 30 μm, 35, 40 μm, 45 μm, or 50 μm. In someexamples, the thickness of the lithium metal negative electrode is about1 μm, about 2 μm, about 3 μm, about 4 μm, about 5 μm, about 10 μm, about15 μm, about 20 μm, about 25 μm, about 30 μm to 35, about 40 μm, about45 μm, or about 50 μm. In some instances, the thickness of the lithiummetal negative electrode is 1 μm. In some instances, the thickness ofthe lithium metal negative electrode is 2 μm. In some instances, thethickness of the lithium metal negative electrode is 3 μm. In someinstances, the thickness of the lithium metal negative electrode is 4μm. In some instances, the thickness of the lithium metal negativeelectrode is 5 μm. In some instances, the thickness of the lithium metalnegative electrode is 6 μm. In some instances, the thickness of thelithium metal negative electrode is 7 μm. In some instances, thethickness of the lithium metal negative electrode is 8 μm. In someinstances, the thickness of the lithium metal negative electrode is 9μm. In some instances, the thickness of the lithium metal negativeelectrode is 10 μm. In some instances, the thickness of the lithiummetal negative electrode is 15 μm. In some instances, the thickness ofthe lithium metal negative electrode is 20 μm. In some instances, thethickness of the lithium metal negative electrode is 25 μm. In someinstances, the thickness of the lithium metal negative electrode is 30μm. In some instances, the thickness of the lithium metal negativeelectrode is 35 μm. In some instances, the thickness of the lithiummetal negative electrode is 40 μm. In some instances, the thickness ofthe lithium metal negative electrode is 45 μm. In some instances, thethickness of the lithium metal negative electrode is 50 μm.

In some examples, including any of the foregoing, the metal negativeelectrode is a sodium (Na) metal negative electrode. In other examples,the metal negative electrode is a zinc (Zn) metal negative electrode.

In some examples, set forth herein is an electrochemical cell having asolid electrolyte.

In some examples, set forth herein is an electrochemical cell having apositive electrode which is separated by the metal negative electrode bythe solid electrolyte positioned there between.

During normal charging and discharging operations in a solid stateelectrochemical cell, ions closer to the interface of the solidelectrolyte may conduct at a rate different from the ions which arecloser to the negative electrode current collector. The imbalance in therates of migration of metal ions within the metal negative electrodecreates inhomogeneities at various surfaces in the metal negativeelectrode (e.g., depressions, cavities, pockets, bubbles, gaps and thelike). These inhomogeneities can occur at the interface of the metalnegative electrode current collector and the metal negative electrode orat the interface of the metal negative electrode and the solidelectrolyte. Inhomogeneities may also arise within the metal negativeelectrode. The aforementioned inhomogeneities reduce ionic conductionthrough the metal negative electrode. The methods described herein allowfor a redistribution of metal in the metal negative electrode therebyreducing or eliminating uneven concentrations of metal. Theredistribution of metal in the metal negative electrode improves contactbetween the metal negative electrode current collector and the metalnegative electrode as well as between the solid electrolyte and themetal negative electrode.

In one instance, during normal charging and discharging operations in asolid state Li-metal negative electrode electrochemical cell describedherein lithium ions closer to the interface of the solid electrolyte mayconduct at a rate different from the lithium ions which are closer tothe negative electrode current collector. The imbalance in the rates ofmigration of lithium ions within the Li-metal negative electrode createsinhomogeneities at the various surfaces in the Li-metal negativeelectrode (e.g., depressions, cavities, pockets, bubbles, gaps and thelike). These inhomogeneities can occur at the interface of the metalnegative electrode current collector and the Li-metal negative electrodeor at the interface of the Li-metal negative electrode and the solidelectrolyte. Inhomogeneities may also arise within the Li-metal negativeelectrode. The aforementioned inhomogeneities reduce ionic conductionthrough the Li-metal negative electrode. The methods described hereinallow for a redistribution of lithium in the Li-metal negative electrodethereby reducing or eliminating uneven concentrations of metal. Theredistribution of lithium in a Li-metal negative electrode improvescontact between the lithium metal negative electrode current collectorand the Li-metal negative electrode as well as between the solidelectrolyte and the Li-metal negative electrode.

Accordingly, in some examples, the metal negative electrode in anelectrochemical cell described herein includes a smoother interfacebetween the solid electrolyte and the metal negative electrode thanotherwise would be present in the absence of charging the metal negativeelectrode according to a method set forth herein.

In some examples, the metal negative electrode includes an interfacebetween the solid electrolyte and the metal negative electrode that hasa surface roughness less than 1 μm.

In some examples, the metal negative electrode includes an interfacebetween the solid electrolyte and the metal negative electrode that hasa surface roughness less than 100 nm.

In some examples, the metal negative electrode includes an interfacebetween the solid electrolyte and the metal negative electrode that hasa surface roughness less than 10 nm.

Provided herein is a method for healing an electrochemical cell, themethod comprising applying mechanical energy (e.g., ultrasonicvibrations) to a metal negative electrode in the electrochemical cell.In some embodiments, the electrochemical cell is in a battery. In someof such instances, the battery is in a vehicle (e.g., a car). In certainexamples, the battery is in use in a car. Also contemplated are methodsfor healing a battery comprising applying mechanical energy to thebattery.

V. Ultrasonic Vibration

In some examples, ultrasonic vibration is applied at a frequency ofbetween 10-1000 kHz. In some examples, ultrasonic vibration is appliedat a frequency of between 10-20 kHz. In some examples, ultrasonicvibration is applied at a frequency of between 20-30 kHz. In someexamples, ultrasonic vibration is applied at a frequency of between30-40 kHz. In some examples, ultrasonic vibration is applied at afrequency of between 40-50 kHz. In some examples, ultrasonic vibrationis applied at a frequency of between 50-60 kHz. In some examples,ultrasonic vibration is applied at a frequency of between 60-70 kHz. Insome examples, ultrasonic vibration is applied at a frequency of between70-80 kHz. In some examples, ultrasonic vibration is applied at afrequency of between 80-90 kHz. In some examples, ultrasonic vibrationis applied at a frequency of between 90-100 kHz. In some examples,ultrasonic vibration is applied at a frequency of between 100-120 kHz.In some examples, ultrasonic vibration is applied at a frequency ofbetween 120-140 kHz. In some examples, ultrasonic vibration is appliedat a frequency of between 140-160 kHz. In some examples, ultrasonicvibration is applied at a frequency of between 160-180 kHz. In someexamples, ultrasonic vibration is applied at a frequency of between180-200 kHz. In some examples, ultrasonic vibration is applied at afrequency of between 200-250 kHz. In some examples, ultrasonic vibrationis applied at a frequency of between 250-300 kHz. In some examples,ultrasonic vibration is applied at a frequency of between 300-350 kHz.In some examples, ultrasonic vibration is applied at a frequency ofbetween 350-400 kHz. In some examples, ultrasonic vibration is appliedat a frequency of between 400-450 kHz. In some examples, ultrasonicvibration is applied at a frequency of between 450-500 kHz. In someexamples, ultrasonic vibration is applied at a frequency of between500-600 kHz. In some examples, ultrasonic vibration is applied at afrequency of between 600-700 kHz. In some examples, ultrasonic vibrationis applied at a frequency of between 700-800 kHz. In some examples,ultrasonic vibration is applied at a frequency of between 800-900 kHz.In some examples, ultrasonic vibration is applied at a frequency ofbetween 900-1000 kHz.

In some examples, the ultrasonic vibration power applied is between0.1-1 mW/cm². In some examples, the ultrasonic vibration power appliedis between 1-10 mW/cm². In some examples, the ultrasonic vibration powerapplied is between 10-100 mW/cm². In some examples, the ultrasonicvibration power applied is between 0.1-1 W/cm². In some examples, theultrasonic vibration power applied is between 1-2 W/cm². In someexamples, the ultrasonic vibration power applied is between 2-3 W/cm².In some examples, the ultrasonic vibration power applied is between 3-4W/cm². In some examples, the ultrasonic vibration power applied isbetween 4-5 W/cm². In some examples, the ultrasonic vibration powerapplied is between 5-6 W/cm². In some examples, the ultrasonic vibrationpower applied is between 20-30 W/cm². In some examples, ultrasonicvibration power is applied of between 6-7 W/cm². In some examples, theultrasonic vibration power applied is between 7-8 W/cm². In someexamples, the ultrasonic vibration power applied is between 8-9 W/cm².In some examples, the ultrasonic vibration power applied is between 9-10W/cm². In some examples, the ultrasonic vibration power applied isbetween 10-20 W/cm². In some examples, ultrasonic vibration is appliedof between 30-40 W/cm². In some examples, the ultrasonic vibration powerapplied is between 40-50 W/cm².

VI. Systems A. Electrochemical Cells With Ultrasonic VibrationGenerators

As shown in FIG. 1 , in some examples, set forth is an electrochemicalcell (100) having a positive electrode (101), a solid electrolyte (102),and a metal negative electrode (103). In some examples, during charging,ultrasonic vibrations (104) are directed to the metal negativeelectrode. This ultrasonic vibration imparts a positive change inenergy, i.e., ΔE, to the metal negative electrode. The increase in ΔE,due to the ultrasonic vibration, mimics a battery heated to elevatedtemperatures. This allows for the charging to occur at a temperaturelower than it otherwise would have occurred at, and without the problemsassociated with low temperature. This allows for fast charging to occurat a temperature lower than it otherwise would have occurred at, andwithout the problems associated with low temperature. Due to theultrasonic vibrations (104), the electrochemical cell (100) can becharged at lower temperature or higher power charging scenarios. Forexample, the battery could be charged at −30° C., −25° C., −20° C., −15°C., −10° C., −5° C., 0° C., 5° C., 10° C., 15° C., 20° C., 25° C., 30°C., 35° C., 40° C., or 45° C. At each of these temperatures, dependingon the amount of ultrasonic vibration imparted to the metal negativeelectrode, the battery could be charged at rates from 0.1 mA/cm² to 20mA/cm². At each of these temperatures, depending on the amount ofultrasonic vibration imparted to the metal negative electrode, thebattery could be charged at C-rates from C/20 to 5C. At each of thesetemperatures, depending on the amount of ultrasonic vibration impartedto the metal negative electrode, the battery could be charged at E-ratesfrom E/20 to 5E.

In some examples, the solid electrolyte protects the metal negativeelectrode (e.g., a Li metal negative electrode) from exposure to ambientconditions. In some examples, the solid electrolyte provides a barrierwhich separates any volatile solvents and/or polymers in theelectrochemical cell from directly contacting the metal negativeelectrode (e.g., a Li metal negative electrode). In some example, thebarrier is the seal that the electrolyte separator makes with the metalnegative electrode (e.g., a Li metal negative electrode).

Due to the ultrasonic vibrations (104), the electrochemical cell (100)can improve (i.e., heal the negative electrode) the battery's lifetimeand safety. For example, after cycling (i.e., charging-discharging) theelectrochemical cell, the metal negative electrode may develop anirregular or uneven surface at the interface with the solid electrolyte.If left untreated, the irregular or uneven surface can result in Lidendrite formation. This Li dendrite formation, if not remedied, canresult in an electrical short between the positive and negativeelectrodes. However, by applying ultrasonic vibrations to the metalnegative electrode, before, during, or after charging theelectrochemical cell, the metal negative electrode can be healed. Thishealed metal negative electrode possesses improved characteristicscompared to the metal negative electrode before it is charged underultrasonic vibration conditions. For example, the interface between themetal negative electrode and the solid electrolyte may be improved, madesmoother, made less rough, and/or in made to have a greater directcontact. Between the metal negative electrode and the solid electrolyte.

Ultrasonic waves can be generated with exterior sources or through wavegenerators attached to battery cell or placed inside a battery cell. Thegenerator, for example, may be a 28 kHz ultrasonic generator fromSTEMiNC SMUG100W28AE with two outputs (50 W directed to each output)(https://www.steminc.com/PZT/en/ultrasonic-generator-auto-energized-100w-28-khz).The transducer, for example, may be a 28 kHz bolt clamped LangevinTransducer from STEMiNC SMBLTD45F28H(https://www.steminc.com/PZT/en/bolt-clamped-langevin-transducer-28-khz).Other piezoelectric transducers may work as well, for example the MurataElectronics North America 7NB-41-1(http://www.digikey.com/products/en/audio-products/buzzer-elements-piezo-benders/160?k=piezoelectric).The transducer was bolted to a CR2032 coin cell. A close coupling of thecoin cell to the transducer is desired; therefore a gel such as anultrasound gel might be used at the interface. The ultrasonic frequencymay be from 0.5-5000 kHz, and the energy input may be from 1 mW/cm² to100 W/cm² per cell cross-sectional area.

B. Coin Cells

FIG. 2 shows a coin cell (202) having a metal negative electrode with apiezoelectric ultrasonic vibration generator (201) attached to an outeredge. This illustration is just one example of the way in which anultrasonic vibration generator may be positioned with respect to a metalnegative electrode. Other embodiments are contemplated by the instantdisclosure.

C. Can Cells

FIG. 3 shows a can cell (302) having a metal negative electrode with apiezoelectric ultrasonic vibration generator (301) attached to an outeredge. This illustration is just one example of the way in which anultrasonic vibration generator may be positioned with respect to a metalnegative electrode. Other embodiments are contemplated by the instantdisclosure.

D. Other Systems

In some examples, provided herein are systems for applying ultrasonicvibration to an electrochemical cell, or series of cells, wherein theultrasonic vibration is applied by a device which is exterior to, or notalready assembled with the electrochemical cells. For example, a carservice station may include ultrasonic vibration instruments includingbut not limited to the instruments set forth herein. These ultrasonicvibration instruments may be used to repair an electric vehicle that isin need of a service. For example, if an electric vehicle had anelectrochemical cell, or series of cells, as traction batteries, and ifthese cells were in need of an improvement with respect to a metalnegative electrode, therein, then the electric vehicle would be charged,while at the service station, using the ultrasonic vibration instrumentsfrom the service station. The service station may regulate thetemperature of the electric vehicle or its electrochemical cells orbattery modules while charging and ultrasonically vibrating theelectrochemical cells. In some examples, ultrasonic vibration is appliedto a pouch cell. In some examples, ultrasonic vibration is applied to apouch cell by a vibration apparatus outside of the pouch. In someexamples, ultrasonic vibration is applied to a pouch cell by a vibrationapparatus inside of the pouch. In further examples, ultrasonic vibrationis applied to a pouch cell by a vibration apparatus inside and outsideof the pouch. In further examples, ultrasonic vibration is applied to apouch cell by a vibration apparatus placed in proximity to the pouch.

E. Diagnostics

The methods and systems herein disclose novel methods of charging ametal negative electrode in combination with the application ofultrasonic vibration to the metal negative electrode. During thesemethods, diagnostic measurements of the electrode or its electrochemicalcell may be observed and/or recorded. During these methods, diagnosticmeasurements of the electrode or its electrochemical cell may beobserved, recorded, transmitted, or received by or from a computerprocessor operatively coupled with computer memory.

In some methods, including any of the foregoing, the methods includemeasuring an electrochemical cell's voltage, current, impedance,resistance, pressure, temperature, evolved gases, or physicaldeformations. In certain methods, the methods include measuring theelectrochemical cell's voltage. In certain methods, the methods includemeasuring the electrochemical cell's current. In certain methods, themethods include measuring the electrochemical cell's impedance. Incertain methods, the methods include measuring the electrochemicalcell's resistance. In certain methods, the methods include measuring theelectrochemical cell's pressure. In certain methods, the methods includemeasuring the electrochemical cell's temperature. In certain methods,the methods include measuring or detecting gases which come from theelectrochemical cell. In certain methods, the methods include measuringor observing physical deformations of the electrochemical cell. Thesephysical deformations may include, but are not limited to, bulging,pitting, or bending of the electrochemical cell. These physicaldeformations may include, but are not limited to, pitting, tears,openings, or cracks in the electrochemical cell.

VII. Examples

Instruments were a 28 kHz ultrasonic generator from STEMiNC SMUG100W28AE(https://www.steminc.com/PZT/en/ultrasonic-generator-auto-energized-100w-28-khz)with two outputs (50 W directed to each output) and a 28 kHz boltclamped Langevin Transducer from STEMiNC SMBLTD45F 28H(https://www.steminc.com/PZT/en/bolt-clamped-langevin-transducer-28-khz).Other piezoelectric transducers may work as well, for example the MurataElectronics North America 7NB-41-1(http://www.digikey.com/products/en/audio-products/buzzer-elements-piezo-benders/160?k=piezoelectric).

Example 1

A solid state electrolyte pellet of 1 mm thickness and 10 mm diameterhad lithium evaporated on both sides with 9 mm diameters. See FIG. 6 .The pellet was placed inside a 2032 coin cell with wave spring pressureconfigured to apply 100-500 psi on the lithium electrodes. The coincells were placed on a hotplate fixture holding the coin cells at 45° C.and 1 mA/cm² of current was passed between the electrodes forapproximately four hours in each direction to pass an equivalentthickness of 20 μm of lithium. This test was repeated 5 times on thedevice with different treatments between each cycle. After the first twocycles, the coin cell was placed at 100° C. for 24 hours. After thethird and fourth cycle, the sample was placed against the ultrasonichorn for less than one second. After the fifth cycle, the sample wasplaced at 45° C. for 24 hours. During the fifth cycle, the sample faileddue to insufficient recovery. It was concluded that the ultrasonictreatment was as effective as a treatment for 24 hours at 100° C., andmore effective than a treatment for 24 hours at 45° C., at restoring theinitial impedance of the cell and prolonging lifetime. The initialimpedances and final impedances are shown in Table 1 below

Initial area-specific Cycle resistance [Ωcm²] Cycle 1, 24 hours at 100°C. 79.5 Cycle 2, 24 hours at 100° C. 82.5 Cycle 3, sonication 86.5 Cycle4, sonication 83 Cycle 5, 24 hours at 45° C. 97

The effectiveness of the sonication is surprising in that it is muchmore time and energy efficient than a heat treatment at recovering theinterface between lithium and the solid state electrolyte pellet.

See FIG. 7 wherein the effect of applying ultrasonic vibration to a Limetal negative electrode is observed.

Example 2

A second coin cell was prepared as above. The procedure of treatment ofthe cell between electrochemical cycles was somewhat different, as shownin Table 2.

Initial area-specific Cycle resistance [Ωcm²] Cycle 1, 24 hours at 100°C. 82.5 Cycle 2, 24 hours at 100° C. 84.8 Cycle 3, 24 hours at 45° C.87.5 Cycle 4, 24 hours at 45° C. 98 Cycle 5, 24 sonication 89.5

The area-specific resistance of the entire cell during cycles 1 and 2are shown in FIGS. 4-5 , respectively.

This Example demonstrated localized heating of metal negative electrodewithout impacting electrochemical performance. This Example demonstratedthat the probability of dendrite generation was reduced when usingsonication periodically. This Example also demonstrated it was possibleto “heal” a Li-metal negative electrode after a high discharge rate byreversing the growth in impedance of the cell.

The embodiments and examples described above are intended to be merelyillustrative and non-limiting. Those skilled in the art will recognizeor will be able to ascertain using no more than routine experimentation,numerous equivalents of specific compounds, materials and procedures.All such equivalents are considered to be within the scope and areencompassed by the appended claims.

1. A method for ultrasonically vibrating a metal negative electrode,comprising providing an electrochemical cell, wherein theelectrochemical cell comprises: a positive electrode, a solidelectrolyte, and and a metal negative electrode; vibrating the metalnegative electrode ultrasonically; and charging the electrochemicalcell, wherein the vibrating and charging occur simultaneously.
 2. Themethod of claim 1, wherein the charging occurs at a temperature lowerthan 80° C., 75° C., 65° C., 60° C., 55° C., 50° C., 45° C., 40° C., 35°C., 30° C., 25° C., 20° C., 15° C., 10° C., 5° C., 0° C., −5° C., −10°C., −15° C., −20° C., −25° C., or −30° C.
 3. The method of claim 1,wherein the charging occurs at a temperature at least higher than −30°C.
 4. The method of claim 1, wherein the metal negative electrode is alithium (Li) metal negative electrode.
 5. The method of claim 1, whereinthe metal negative electrode is a sodium (Na) metal negative electrode.6. The method of claim 1, wherein the metal negative electrode is a zinc(Zn) metal negative electrode.
 7. The method of claim 1, wherein thesolid electrolyte is a sulfide-based electrolyte, a garnet-basedelectrolyte, or a borohydride-based electrolyte.
 8. The method of claim1, further comprising applying a pressure to the metal negativeelectrode.
 9. The method of claim 8, wherein the applied pressure is atleast 10, 20, 30, 40, 60, 70, 80, 90, 100, 200, 300, 400, 500, 600, 700,800, 900, 1000, 2000, 3000, or 4000 pounds per square inch (PSI). 10.The method of claim 8, wherein the applied pressure is less than 600,500, 400, 300, 200, 100, 80, 70, 60, 50, 40, 30, 20, or 10 PSI.
 11. Themethod of claim 1, wherein the solid electrolyte is a sulfide-basedelectrolyte.
 12. (canceled)
 13. A method of charging a battery having ametal negative electrode, the method comprising providing a batteryhaving less than a full charge; vibrating the battery at ultrasonicfrequencies; and charging the battery, wherein the vibrating andcharging occur concurrently.
 14. (canceled)
 15. The method of claim 13,further comprising applying a pressure to the metal negative electrode.16. The method of claim 13, wherein the applied pressure is at least 10pounds per square inch (PSI), 20 PSI, 30 PSI, 40 PSI, 50 PSI, 60 PSI 70PSI, 80 PSI, 90 PSI, 100 PSI, 200 PSI, 300, PSI 400 PSI, 500 PSI, 600PSI, 700 PSI, 800 PSI, 900 PSI, 1000 PSI, 2000 PSI, 3000 PSI, or 4000PSI.
 17. The method of claim 13, wherein the applied pressure is lessthan 600 PSI, 500 PSI, 400 PSI, 300 PSI, 200 PSI, 100 PSI, 80 PSI, 70PSI, 60 PSI, 50 PSI, 40 PSI, 30 PSI, 20 PSI, or 10 PSI.
 18. The methodof claim 17, where the applied pressure is 300 PSI or less.
 19. Themethod of claim 13, wherein the current at which the charging occurs isat least 1 mA/cm², 2 mA/cm², 3 mA/cm², 4 mA/cm², 5 mA/cm², 6 mA/cm², or10 mA/cm².
 20. The method of claim 13, wherein the method furthercomprises measuring an electrochemical cell's voltage, current,impedance, resistance, pressure, temperature, evolved gases, or physicaldeformations.
 21. An electrochemical cell having a Li-metal negativeelectrode made by the method of claim
 1. 22. An electrochemical cellhaving a Li-metal negative electrode healed by the method of claim 1.23. (canceled)
 24. The method of claim 1, wherein the electrochemicalcell is in a battery.
 25. The method of claim 1, wherein the battery isin a car.
 26. The method of claim 1, wherein the battery is in use in acar.